Autonomic nervous system dysfunction in children with severe tetanus: dissociation of cardiac and vascular sympathetic control

Abstract

The medical records of ten pediatric patients with a clinical diagnosis of tetanus were reviewed retrospectively. The heart rate and blood pressure of all tetanus patients were measured noninvasively every hour during the first two weeks of hospitalization. Six of ten tetanus patients presented clinical evidence of sympathetic hyperactivity (group A) and were compared with a control group consisting of four children who required mechanical ventilation for diseases other than tetanus (group B). Heart rate and blood pressure simultaneously and progressively increased to a maximum by day 7. The increase over baseline was 43.70 ± 11.77 bpm (mean ± SD) for heart rate (P<0.01) and 38.60 ± 26.40 mmHg for blood pressure (P<0.01). These values were higher and significantly different from those of the control group (group B) at day 6, which had an average heart rate increase over baseline of 19.35 ± 12.26 bpm (P<0.05) and blood pressure of 10.24 ± 13.30 mmHg (P<0.05). By the end of the second week of hospitalization, in group A the increase of systolic blood pressure over baseline had diminished to 9.60 ± 15.37 mmHg (P<0.05), but the heart rate continued to be elevated (27.80 ± 33.92 bpm, P = NS), when compared to day 7 maximal values. The dissociation of these two cardiovascular variables at the end of the second week of hospitalization suggests the presence of asymmetric cardiac and vascular sympathetic control. One possible explanation for these observations is a selective and delayed action of tetanus toxin on the inhibitory neurons which control sympathetic outflow to the heart.

Autonomic nervous system instability, tetanic necrosis of the heart and myocardial TNFα expression in a tetanus fatal case

“…Considering the possibility of detecting early signs of sympathetic overactivity by the Holter, early treatment of this syndrome using morphine, magnesium sulfate, labetalol or fentanyl could result in a better clinical progression, lessening the effects not only of hypercatecholaminemia before they become clinically manifest, but also the severe complications resulting from sudden variations in blood pressure and heart rate [2,7].…”

Tetanus: pathophysiology, clinical signs, diagnosis, and update on new treatment modalities

“…1,[33][34][35] Autonomic signs do not usually begin until several days after the rigidity has set in and may persist for 1-2 weeks. 12,21,36 Basal catecholamine levels can be up to 10 times the normal level during an autonomic storm. 12,21,36,37 A dramatic illustration of this increase is the rupture of an aneurysm secondary to hypertension in a person with tetanus.…”

“…12,21,36 Basal catecholamine levels can be up to 10 times the normal level during an autonomic storm. 12,21,36,37 A dramatic illustration of this increase is the rupture of an aneurysm secondary to hypertension in a person with tetanus. 34 Although reported in veterinary medicine, autonomic dysfunction is not recognized as frequently in animals as it is in humans.…”

“…34 Although reported in veterinary medicine, autonomic dysfunction is not recognized as frequently in animals as it is in humans. 23,[36][37][38] It is unclear if this is related to inadequate monitoring, pathophysiological differences between humans and veterinary species, or a combination of the 2.…”

“…71 In humans with tetanus, autonomic dysfunction is a potentially serious sequela that is characterized by periods of tachycardia and hypertension occasionally alternating with bradycardia and hypotension. [35][36][37] Sympathetic overactivity, the most devastating aspect of autonomic dysfunction, manifesting as extreme hypertension and tachycardia with increased systemic vascular resistance, is very challenging to treat. There has been much interest in drugs that would control the autonomic dysfunction without overly sedating the patient.…”